diff options
Diffstat (limited to 'stdlib/erand48_r.c')
-rw-r--r-- | stdlib/erand48_r.c | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/stdlib/erand48_r.c b/stdlib/erand48_r.c new file mode 100644 index 0000000000..86d2f734d9 --- /dev/null +++ b/stdlib/erand48_r.c @@ -0,0 +1,52 @@ +/* Copyright (C) 1995 Free Software Foundation, Inc. +This file is part of the GNU C Library. +Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, August 1995. + +The GNU C Library is free software; you can redistribute it and/or +modify it under the terms of the GNU Library General Public License as +published by the Free Software Foundation; either version 2 of the +License, or (at your option) any later version. + +The GNU C Library is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, +Boston, MA 02111-1307, USA. */ + +#include <errno.h> +#include <math.h> +#include <stdlib.h> + +int +erand48_r (xsubi, buffer, result) + unsigned short int xsubi[3]; + struct drand48_data *buffer; + double *result; +{ + int i; + + /* Be generous for the arguments, detect some errors. */ + if (result == NULL) + { + errno = EFAULT; + return -1; + } + + /* Compute next state. */ + if (__drand48_iterate (xsubi, buffer) < 0) + return -1; + + *result = 0.0; + for (i = 4 / sizeof (unsigned short int); i >= 0; --i) + { + double factor = ldexp (1.0, (i - 6) * sizeof (unsigned short int)); + + *result += factor * (double) xsubi[i]; + } + + return 0; +} |